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Of Mice and Men

It’s human nature to find someone else to blame. When bagged spinach turned deadly a couple years ago, a panicked quest was on to guarantee food safety. Food growers began taking extraordinary precautions to prevent a resurgence of the E. coli outbreak. The reputed villains of the tainted spinach epidemic—as well as the victims of some of the resulting overzealous food safety efforts—are wild animals, despite the likelihood that our overuse of antibiotics in livestock, and not contamination by wildlife, is actually at fault for the spread of the dangerous bacterium.

It all started on September 14, 2006, the day the US Centers for Disease Control and Prevention (CDC) announced that a virulent variety of E. coli , strain O157-H7, had infected and sickened fifty people. E. coli can cause cramps, diarrhea, and ultimately kidney failure. The Federal Department of Agriculture reported that bagged spinach probably caused the outbreak and urged consumers not to purchase or eat fresh spinach products. By the first week of October, 204 people had fallen ill in 26 states, and three had died. Scientists traced the pathogen to Natural Selection Foods (commonly known as Earthbound Farms), in San Juan Bautista, California.

An FDA recall sent spinach sales sliding so low that the industry lost around $80 million; the recall hit California growers, who produce 75 percent of all leafy greens, especially hard. Grocery store owners and national retailers like Wal-Mart pulled all bagged spinach dated between August 17 and October 1. No fresh spinach was sold for five days.
The overwhelming scope of the outbreak and the deadly nature of O157-H7 spurred intensive media coverage, which left leafy greens growers and processors scrambling to assure their products’ safety. By 2007, the beleaguered bagged greens industry, nervous over profit losses, potential lawsuits, and an increasing pathogen problem, united to centralize food safety standards. Nearly every greens producer in the state signed onto the optional California Leafy Green Products Handler Marketing Agreement (LGMA), which sets safety and sanitation standards for produce handlers. Today the LGMA has 120 certified participants who together produce 99 percent of the leafy greens in California.

Although the LGMA has been successful in increasing sales and lowering contamination, an over-zealous application of its safety advisories has produced another result: a war against wildlife and a reversal of hard-won efforts to encourage farmers to conserve wild areas near cultivated fields. Perhaps because the FDA has not yet determined the original source of 2006’s deadly E. coli strain or its mode of transport to the contaminated
fields, the industry has adopted a zero-sum approach to food safety. Everything is a potential culprit and must be sterilized, even nature.

Some conventional processors and national retailers, using the LGMA’s more benign metrics as a guide, began imposing highly stringent regulations, coined “super metrics,” in an attempt to create “sterile farms” and remove all risk of pathogen contamination. Mice, frogs, birds, pigs, and deer have been incriminated as potential pathogen vectors, and auditors and food safety consultants demand that farmers tear out hedgerows and other vegetation, kill wildlife, and erect fences in the name of consumer safety. In an attempt to remove risk from a natural and inherently variable product, the bagged greens industry has pitted human health against the environment.

While these ordered features, designed to keep wildlife out, conform to the efficiency requirements of leafy green processors and distributors, fertilizing and processing methods could spread disease far more efficiently than, say, a mouse. For example, contaminated irrigation water is a likely E. coli vector. Pathogen-carrying water sprayed on lettuce fields before harvest can make it into processed, ready-to-eat bags despite the chlorine baths used by processing plants. Researchers have also suggested that fields fertilized with improperly treated raw manure from livestock could spread contamination, as can feces deposited by wild animals.

Large-scale growers use machines to cut thousands of pounds of leafy greens at the stem and ship them to processing plants, where tons of lettuces from various farms are washed together and sealed in plastic bags. Millions of bags of greens are produced each week. One load of fresh-cut lettuce carrying E. coli pathogens could contaminate thousands of bags before being shipped across the nation, and the technologically advanced bags keep greens fresh for over two weeks, making them effective incubators for the bacterium.

According to the Community Alliance with Family Farmers and the FDA, since 2002, all E. coli outbreaks associated
with lettuce and spinach have occurred in processed, fresh-cut, bagged greens. “We have a record of fourteen outbreaks from 2002 [to today] linked to fresh-cut leafy greens,” says FDA press officer Stephanie Kwisnek. “They were all in sealed bags.”

Killer bugs and wildlife
Hundreds of strains of E. coli live in the environment and in our intestines, many of which pose little threat to human health. Serotype O157-H7 is a nasty new pathogen, a likely product of antibiotic use in the industrial beef industry. Detected for the first time about thirty years ago, O157-H7 is virulent, highly resistant, and, unfortunately, is often found in our food, particularly in meat products. While the pathogen is eliminated easily by heat (industry insiders call cooking a “kill step”), leafy greens remain a possible carrier since they are eaten raw.
Scientists and health officials widely recognize Concentrated Animal Feeding Operations (CAFOs) as the primary source of the bacteria. Highly populated cattle-growing operations house and feed thousands of animals for at least 45 days before slaughter. According to the CDC, since 2003 the nation’s 238,000 feedlot operations have produced 500 million tons of manure, and anywhere from two to fifty percent of a herd can carry O157-H7 and shed the bacteria in their poop. In a public presentation last November, Dr. Robert S. Lawrence, director of the Center for a Livable Future at the John Hopkins Bloomberg School of Public Health, said the high concentration of stressed animals, sub-optimal hygiene, and the abundant use of antibiotic treatments encourage O157-H7 contaminations to spread quickly through feedlot animals. “The fecal veneer that covers the entire earth increases dramatically in a feedlot,” quips Dr. Lawrence.

Massive cattle feedlots may be the top reservoir of E. coli O157-H7, but it is still uncertain how the pathogens travel to farms. However, some farmers fear that wild animals living near these feedlots are ingesting contaminated feces and then depositing O157-H7 on or near a leafy greens farms or water sources, thereby spreading the contagion. The FDA’s Kwisnek points out that for the 2006 outbreak, “The exact cause has not been determined and probably never will be. … However, some of the waterways were contaminated with cattle and wildlife feces, so the farmers are taking action.”

In order to mitigate all possible vectors, Scott Horsfall, CEO of the LGMA, says that food safety auditors focus on potential causes of contamination: worker sanitation, manure, water, and wildlife. “There is a certain amount of scientific evidence that wildlife can be a carrier of E. coli,” says Horsfall. “So they are definitely one of the risk factors.”

“Wildlife must certainly be considered as a potential vector for E. coli,” agrees Will Daniels, vice president of quality, food safety and organic integrity at Earthbound Farms. “The problem is that we grow produce basically in the wild… The idea is to identify if there is a risk and then develop realistic control measures.” Yet although the producers’ and auditors’ concern is real, the science some have cited to justify the removal of wildlife is contradictory. Diana Stuart, a grad student in the Environmental Studies Department at UC Santa Cruz, has compiled statistics from a variety of studies that show most wild animals have a low chance of carrying E. coli: deer (up to two percent), wild birds (up to one percent), and rodents (none). Feral pigs are the only wild animals proven to be significant vectors of E. coli, with up to a fifteen percent carrier rate.

Field of contradictions
Many privately hired food safety auditors and consultants are attacking nature with unwarranted zeal. A 2007 Resource Conservation District of Monterey County Survey reports that of 181 responding growers, operating a combined 140,000 acres of row cropland, 47.7 percent were asked to discourage the presence of wildlife, and nearly all of these—40.7 percent of the 181 responding growers—complied.

“Discouraging wildlife” included removing filter strips, hedgerows, grassy waterways, and windbreaks to create large, sterile buffer zones between row crops and along field and property edges. From a conservation perspective, growing native plants along farm boundaries is highly beneficial, and environmental protection agencies have universally promoted the practice over the last two decades. It is intended to improve water quality, reduce erosion, increase microbial diversity in the soil, and provide habitat for native species. Yet about fifteen percent of the responding growers reported that auditors advised them to remove ponds and waterways, including tailwater recovery ponds and catch basins, and half of those growers complied. Nearly all of the surveyed farmers had adopted at least one practice—typically the removal of surrounding habitat vegetation—to deter the presence of mice, birds, frogs, pigs, and deer on farms.

Ironically, the removal of vegetation may increase the presence of pathogens in waterways. At a Wild Farm Alliance-
sponsored Food Safety Teach-In in San Francisco last November, Danny Marquis—a conservationist at the Natural Resources Conservation Service of Monterey County—said that conservation practices like hedgerows and filter strips can intercept airborne dust, chemical drift, and detain water-borne pathogens. Removing tailwater systems and sediment basins—practices that catch irrigation runoff and help filter the water before it re-enters the ecosystem or is reused on the farm—worsens water quality, increases sediment, and causes erosion. Even Natural Food Selections, which adheres to some of the strictest processing standards within its plant, acknowledges that wildlife is essential to a healthy environment and farm. “We need to take a little more realistic and progressive approach to mitigation,” says Earthbound’s Daniels. “We consider wildlife an integral part of the process.”

Even LGMA’s Horsfall notes that some of the safety metrics are over-the-top. “There are conflicting requirements out there causing a lot of confusion and I think there are excessive requirements, based on what I know,” says Horsall. “I think what everyone needs to focus on is setting one set of scientific requirements.”

Conflict of cultures
Dale Coke, one of a handful of farmers who refused to join the LGMA, has been selling organic greens mixes for over twenty years. The contrast in farming styles between a conventional farm and one of Coke’s fields is appreciable. Instead of straight, ordered rows, a cilantro patch abuts lettuce rows and workers pick winter greens by hand. Coke worries about the new leafy greens marketing environment and the stringency of the super metrics. “If growers get used to the unwarranted metrics you could get more sets of practices that mean nothing,” he explains. “And if they get some kind of consistency that they come up with for all commodities, it would be even worse.”

At the heart of the issue is a conflict of culture: Everyone cares about food safety, but problems arise because so few people know or care about farming. The result is a set of metrics that farmers think are irrational. Ken Kimes, who grows sprouts and other microgreens in Aptos, has dealt with food safety regulations for years. He believes that most auditors struggle with the idea that farms are, after all, outside. “You know, having birds flying around, it’s deadly!” he says dryly. “I had one [auditor] tell me that every time a bird pooped, it’s salmonella.”

Farmers are quick to point out that some things can never be controlled completely. Although agriculture has historically sought to control nature by isolating and harvesting productive plants and killing pests, respect and understanding of the natural world has been generally accepted as well.

Tom Willey, owner of T&D Willey Farm in Madera, feels the problem is at root one of increasing incidence of virulent pathogens in the industrial meat business, and that removing wildlife from farmland misses the point. He blames our nation’s obsession with sterility and the beef industry’s over-reliance on antibiotics for burgeoning superbugs. “The whole food safety baloney is not gonna go away,” Willey says. “It’s going to continue raising its ugly head. And I think a reason for that is because the industrial animal industry, through their production practices, are creating some dangerous microbes that small farms have a hard time protecting themselves against.” Reducing the predominance of O157-H7 on feedlots would require a reworking of the industrial cattle industry and the abandonment of excessive antibiotic use in livestock, regulations that fall under the domain of the USDA.

The risk associated with bagged greens is reducible, but regardless of the industry’s attempt to control surrounding wildlife, it’s never been entirely stamped out. Last September, 45 people in five states were sickened by bagged fresh-cut iceberg lettuce. The FDA has traced the source of the pathogen back to California, but the story got so little attention that neither the FDA nor the CDC even mention it on their Web sites. Four months later, the LGMA does not even know if one of its members was responsible, leaving little confidence that its measures are working.
Despite two years of regulations, E. coli outbreaks in bagged leafy greens have yet to be eradicated. Rather than reviewing, adjusting, and updating the self-regulatory framework of the LGMA and leafy greens processors, the FDA has taken a hands-off approach to industrial regulation and has also failed to foster cooperation between the agencies that oversee the meat and produce industries and that set environmental standards. The consumer is left to decide how much risk to take when eating pre-washed greens—and at what environmental cost those greens are produced. “It’s hard to talk about tolerating a certain amount of risk in food to save the environment or be sensible,” says farmer Kimes. “It’s kind of like everybody has to be on the zero-risk path. And this is where the burden comes in for the small farmer, and actually the large farmers too… there is really no way to mitigate and create zero risk.